+++ /dev/null
-
-Here are general trigger functions provided as workable examples
-of using SPI and triggers. "General" means that functions may be
-used for defining triggers for any tables but you have to specify
-table/field names (as described below) while creating a trigger.
-
-1. refint.c - functions for implementing referential integrity.
-
-check_primary_key () is to used for foreign keys of a table.
-
- You are to create trigger (BEFORE INSERT OR UPDATE) using this
-function on a table referencing another table. You are to specify
-as function arguments: triggered table column names which correspond
-to foreign key, referenced table name and column names in referenced
-table which correspond to primary/unique key.
- You may create as many triggers as you need - one trigger for
-one reference.
-
-check_foreign_key () is to used for primary/unique keys of a table.
-
- You are to create trigger (BEFORE DELETE OR UPDATE) using this
-function on a table referenced by another table(s). You are to specify
-as function arguments: number of references for which function has to
-performe checking, action if referencing key found ('cascade' - to delete
-corresponding foreign key, 'restrict' - to abort transaction if foreign keys
-exist, 'setnull' - to set foreign key referencing primary/unique key
-being deleted to null), triggered table column names which correspond
-to primary/unique key, referencing table name and column names corresponding
-to foreign key (, ... - as many referencing tables/keys as specified
-by first argument).
- Note, that NOT NULL constraint and unique index have to be defined by
-youself.
-
- There are examples in refint.example and regression tests
-(sql/triggers.sql).
-
- To CREATE FUNCTIONs use refint.sql (will be made by gmake from
-refint.source).
-
-# Excuse me for my bad english. Massimo Lambertini
-#
-#
-# New check foreign key
-#
-I think that cascade mode is to be considered like that the operation over
-main table is to be made also in referenced table .
-When i Delete , i must delete from referenced table ,
-but when i update , i update referenced table and not delete like unmodified refint.c .
-
-I made a patch that when i update it check the type of modified key ( if is a text , char() i
-added '') and then create a update query that do the right think .
-
-For my point of view that policy is helpfull because i do not have in referenced table
-loss of information .
-
-
-In preprocessor subdir i have placed a little utility that from a SQL92 table definition,
-it create all trigger for foreign key .
-
-
-the schema that i use to analyze the problem is this
-
-create table
-A
-( key int4 not null primary key ,...) ;
-create table
-REFERENCED_B
-( key int 4 , ... ,
-foreign key ( key ) references A --
-);
-
-
-
-
-
-
+++ /dev/null
--- Note the syntax is strict because i have no time to write better perl filter.
---
--- [blank] is 1 blank
--- at the end of an interesting line must be a [,] or [--]
--- [ending] must be a , or --
---
--- foreign[blank]key[blank]([blank]keyname,..,keyname[blank])[blank]references[blank]table[blank][ending]
---
--- step1 < example.sql | step2.pl > foreign_key_triggers.sql
---
--- step1.c is a simple program that UPPERCASE ALL . I know that is simple implementing in Perl
--- bu i haven't time
-
-
-CREATE TABLE
-gruppo
-(
-codice_gruppo int4 NOT NULL,
-descrizione varchar(32) NOT NULL
-primary key ( codice_gruppo )
-
-) ;
-
---
--- fa_parte : Appartenenza di una Azienda Conatto o Cliente ad un certo GRUPPO
---
-
-CREATE TABLE
-fa_parte
-(
-codice_gruppo int4 NOT NULL,
-codice_contatto int4 NOT NULL,
-
-primary key ( codice_gruppo,codice_contatto ) ,
-foreign key ( codice_gruppo ) references gruppo --
-);
-
+++ /dev/null
-#include <stdio.h>
-
-char *
-strtoupper(char *string)
-{
- int i;
-
- for (i = 0; i < strlen(string); i++)
- string[i] = toupper((unsigned char) string[i]);
- return string;
-}
-
-
-
-void
-main(char argc, char **argv)
-{
- char str[250];
- int sw = 0;
-
- while (fgets(str, 240, stdin))
- {
- if (sw == 0)
- printf("%s", strtoupper(str));
- }
-
-}
+++ /dev/null
-#!/usr/bin/perl
-
-##
-## MAIN
-##
-$table_name="";
-$old_name="";
-$references_table="";
-$references_column="";
-$is_create=0;
-
-
-
-while ( <> )
-{
- chop;
- $str=$_ ;
-
- if ($is_create == 1) {
- $table_name=$str;
- $is_create=2;
- }
- if ( $str =~ /^CREATE TABLE/ ){
- $is_create=1;
- }
- if ($is_create == 2) {
- if ($str =~ /^FOREIGN KEY/){
- ($d1,$d2,$d3,$columns,$d4,$d5,$references_table,$d6) = split (/ /,$str,8);
- #printf "Table $table_name $columns $references_table\n";
-
- if ($table_name ne $old_name ){
- printf "--\n-- Trigger for $table_name\n--\n\n";
- }
-
- foreach $i ( split(/,/ , $columns ) ){
- print "CREATE INDEX I_$table_name";
- print "_$i ON $table_name ( $i ) ;\n";
- }
-
- printf "\nCREATE TRIGGER T_P_$table_name";
- printf "_$references_table BEFORE INSERT OR UPDATE ON $table_name FOR EACH ROW\n" ;
- printf "EXECUTE PROCEDURE\n";
- printf "check_primary_key(";
- $val=0;
- foreach $i ( split(/,/ , $columns ) ){
- print "'$i',";
- $val=$val+1 ;
- }
- print "'$references_table',";
-
- $t=1;
- foreach $i ( split(/,/,$columns ) ){
- print "'$i'";
- if ( $t < $val ) {
- printf ",";
- }
- $t=$t+1;
- }
- print " );\n\n";
-
- printf "CREATE TRIGGER T_F_D_$references_table";
- printf "_$table_name BEFORE DELETE ON $references_table FOR EACH ROW\n" ;
- printf "EXECUTE PROCEDURE\n";
- printf "check_foreign_key(1,'cascade',";
- $val=0;
- foreach $i ( split(/,/ , $columns ) ){
- print "'$i',";
- $val=$val+1 ;
- }
- print "'$table_name',";
-
- $t=1;
- foreach $i ( split(/,/,$columns ) ){
- print "'$i'";
- if ( $t < $val ) {
- printf ",";
- }
- $t=$t+1;
- }
- print " );\n\n";
-
- printf "CREATE TRIGGER T_F_U_$references_table";
- printf "_$table_name AFTER UPDATE ON $references_table FOR EACH ROW\n" ;
- printf "EXECUTE PROCEDURE\n";
- printf "check_foreign_key(1,'cascade',";
- $val=0;
- foreach $i ( split(/,/ , $columns ) ){
- print "'$i',";
- $val=$val+1 ;
- }
- print "'$table_name',";
-
- $t=1;
- foreach $i ( split(/,/,$columns ) ){
- print "'$i'";
- if ( $t < $val ) {
- printf ",";
- }
- $t=$t+1;
- }
- print " );\n\n";
-
- if ($table_name ne $old_name ){
- printf "-- ********************************\n\n\n";
- }
- $old_name=$table_name ;
-
-
-
-
- }
- }
- if ($str =~ /^\)\;/ ) {
- $is_create = 0 ;
- }
-
-}
-
-
-
-
-
-
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